Adjustable stand for draftsmen or the like



Aug. 29, 1944. e. E. FROELICH 2,356,924

ADJUSTABLE STAND FOR DRAFTSMEN OR THE LIKE Filed June 22, 1942 3Sheets-Sheet l J0 J7 Z7 1 ll I 1944; e. E. FROELICH 2,355,924

ADJUSTABLE STAND FOR DRAFTSMEN OR THE LIKE Filed June 22, 1942 3 sh t -s2 +3 V .39 4a 44 22 K A 5 .517 37 J6 H 39 4 A .36

Aug. 29, 1944. e. E. FROELICH ADJUSTABLE STAND FOR DRAFTSMEN OR THE LIKEs Sheets-Sheet 3 Filed June 22, 1942 fizverar Gear 6 Efiaelc'c PatentedAug. 29, 1944 OFFICE I ADJUSTABLE STAND FOR DRAFTSMEN OR THE LIKE GeorgeE. Froelich, Two Rivers, Wis., assignor to Hamilton ManufacturingCompany, Two Rivers, Wis., a corporation of Wisconsin Application June22, 1942, Serial No. 447,969

7 Claims.

This invention relates to adjustable stands for draftsmen or the likeandmore particularly of the class broadly described and claimed in myprior Patent No. 1,956,546 ofApril 24, 1934.

The present invention is also specially adapted for use with devicesshown in my co-pending application Serial No. 351,381, filed August. 4,1940, which has issued as Patent No. 2,312,636 granted March 2, 1943,and including an arcuate bar and a torsion spring normally gripping thebar to provide a friction clutch mechanism usable for adjusting tworelatively movable members.

Among other objects, the present invention aims to provide a structureof this type of enhanced simplicity and economy of manufacture, while atthe same time affording the many advantages attendant to such structurein which the stand has two Working surfaces, one afforded by the top ofthe base, which may be a table or desk having drawers in one facethereof, and the other working surface by a drafting board mounted atthe other face thereof, the drafting board being readily adjustable byatouch of the foot or hand of the. draftsman to regulate both its heightand its inclination, for enhanced comfort and speed of work.

These and other objects and advantages will beapparent from thefollowing description, taken together with the accompanying drawings,,in which- Figure 1 is a side view of a stand embodying the presentimprovements;

Figure 2 is a front view of the left-hand side of the structure shown inFig. 1 looking at Fig. 1 from the left somewhat enlarged;

- Figure 3 is a section taken on the line 3.-3 of Fig. 2;

Figure 4 is a section taken on the irregular line 44 of Fig. 3 but asthe structure appears at the right-hand side of Fig. 1, looking at Fig;1 from the left;

Figure 5 is a detail perspective view of parts shown in the earlierreferredto figures and still further enlarged;

Figure 6 is a view similar to Fig. 1 but showing another selectiveposition of the parts; and

Figure 7 is also a view similar to Fig. 1 but showing still anotherselective position of the parts. 1

In the illustrative construction shown in the drawings, the numeral I0represents a base for the drawing board II, which is mounted on strutsI2, the latter being articulated as by links I3 and I4 with the'desk I0.

The desk I 0 may have the usual side walls It and I6, and working topsurface I1, and may be reinforced near its bottom by a cross-piece I8. Adrawer I 9, shownpartially open in Fig. 1, may be located accessible atone face of the desk I0,

I that is, what may here be called its rear face.

who may be using the drawing board I I at this face of the stand. Itwill be observed from the drawings and particularly looking at Figs. 2and 4 together, that there are here shown a pair of struts l2, a pair oflinks I3 and a pair of links M, two links for each strut. The strutsadjacent 1 their tops mount the drawing board I I in a manner which willnext be described.

. The drawing board I I comprises a drawing board proper 2| having asmooth fiat working surface 22 suitable for making mechanical drawingsor the like thereon. To the underside of the drawing board proper 2Iadjacent each side margin thereof are secured a pair of cleats 2-3.Pivoted adjacent the upper end of each of the struts I2, which may be ofWood to conserve metal, is

here shown a metal bracket member 24, the shape of which is best seenfrom Fig. 5. The leg 25 of the bracket member 24 is perforated as at 26to pass therethrough the pivot bolt 27 which also passes through thestrut I2 adjacent its upper end as best seen in Fig. 4, the bracketbeing upon the inner face of the strut. At its free end the bracket (hasanoffset portion 28 through holes 29in which screws pass into the outerface of the cleat 23 of the drawing board. For reinforcement an angleplate 30 may be riveted to the bracket 24 as at 3I to underlie the loweredge of the'cleat 23 and, through holes 32 in which plate, screws 33 maypass into the cleat. Thus the drawing board is securely but rotativelymounted on'the struts. The bent portions 34 and 35 of the bracket 24 mayact as stops to limit backward rotation of the drawingboard'on thestruts by contactin with the struts when the drawing board is rotated toa horizontal position.

Drawn from the offset portion 28 of the bracket 24, I have shown 'acylindrical bushing part 36 which enters a through passage 31 in thecleat 23 and forms a bearing for areduced end of a trunnion 38, theother end Of which has passed over. it a hollow rock shaft 39 which thusconnects the two trunnions 38 .at each side of the structure, thetrunnions forming end plugs for the shaft. Adjacent each end of thehollow rock shaft 39, an arm 40 passes through the rock shaft and alsoadvantageously through the trunnion 38, keying the rock shaft andtrunnions together for common rotation in the bracket members 24. Sincethe rock shaft is slightly larger in diameter than the through passages31, lateral movement of the rock shaft is limited.

In each reduced end of the trunnion 38 is anchored axially the ends 4|and 42 of a torsion spring 43 which encircles in somewhat wrapped aroundrelation an arcuate bar 44 fixed at one end, as at 45, to the upperextremity of the strut I2, and, at its lower end, as at 46, to anintermediate part of the strut, the bar 44 extending in bowed formationoutwardly of the strut toward the front face of the stand. The torsionsprings 43 normally grip the bars 44 with sufficient friction to preventunintentional movement of the torsion springs on the bars, and to assistin maintaining the torsion springs and at the same time the rock shaft39, in gripping position, the arms 49 may each have their outer endsconnected with a tension coil spring 41, the other end of which ishooked as at 48 to a drawing board cleat 23. To rotate the rock shaft 39in the opposite direction to bias the parts to loosen the grip of thetorsion springs 43 on the bars 44 against the pull of the tensionsprings 41, a hand lever 49 is provided in the form of a metal loopsecured at its ends to the rock shaft 39 as at 50 (Figs. 2 and 3). Theouter end of the hand lever 49 lies beneath the drawing board 2| and isaccessible at the proximate side of this board, where a stirrup guardsthe lever end.

So constructed and arranged, manual movement of the lever 49 in thestirrup 5| toward the board 2| will release the torsion springs 43 onthe bars 44 and permit rotation of the brackets 24 carrying the draftingboard H to any selected position from the horizontal as shown in Fig. 1toward the vertical as shown in Fig. 6. Upon release of the lever 49,the inherent resilience of the torsion springs 43, aided by the tensionsprings 41, restores the gripping effect of the torsion springs 43 onthe bars 44 and maintains the board II at its selected inclination mostconvenient to the draftsman. For example, with the adjustmentshown inFig. 6, the draftsman may use the board while seated on an ordinarychair.

Turning now to the means for lowering and raising the struts l2 toadjust the elevation of the board II, it will be observed that the linksl3 and I4 are pivoted to the strut 12 at each side of the stand at 52and 53 respectively and to the desk H] at 54 and 55 respectively. Thepivot points 52, 53, 54 and 55 together define a parallellogram. In thisinstance, the links 13 and [4 may also conveniently be of wood and thepivots 52, 53 and 55 provided by pivot bolts of these members, metalwashers 56 being interposed between the moving parts to minimizefriction. In the case of the pivot 54, this is here shown constituted bya metallic rock shaft of this number which runs cross-wise of the. desk19 to connect the links 13 at each side of the desk. At each side, therock shaft 54 passes through the links 13 andis journaled in a pivotplate 51, secured, as by screws 58 to a wood upright 59 carried by theinner face of each desk side l5 and i6, and fastened thereto as by thethrough bolts 69. The upright 59 is recessed as at 6| to journal therock shaft 54 therein as'best shown in Fig. 4, and the rock shaft iskeyed to the link 13 as by a metal boxing '82 surrounding the rock shaftand welded thereto as at 63, the boxing also lapping the link 13 andbeing secured thereto as by screws 84. Thus the rock shaft 54, boxings62, and links [3 rotate as a unit in the pivot plates 51. It will beseen that the uprights 59 also carry the pivots 55 at the inner ends ofthe lower links l4, the uprights being spaced from the inner face of thedesk by filler blocks 65 to permit free play of the links I4 on theirpivots 55. Since the links l3 and I4 thus define a parallelogram in allpivoted positions, the strut l2 will always remain vertical. To assistin stabilizing the structure at both sides of the stand, a plank 66 maybe disposed across the inner edges of the struts l2 and suitablyfastened to each strut.

Selective adjustment means for the elevation of the struts l2, includesan adaptation of the torsion spring and bar mechanism already describedwith reference to the adjustment means for the inclination of the boardII, and in the case of the struts includes an arcuate bar 81 secured atone end as by screws 68 to each link l4 and at its other end as byscrews .69 to an angular continuation 18 of the link l4,thiscontinuation extending upwardly so that the an cuate bar 61 forms anupper quadrant of a circle within the desk ID. A bracket 1| is securedto the upright 59, as by screws 12 just above the link continuation 10and clear of the latter. This bracket 1| functions somewhat similarly tothe bracket 24 and has an offset portion 13 which is spaced from theupright 59 and laps thearcuate bar 61. .In this offset bracket portion13 at each side of the desk is journaled a rock shaft 14 as by trunnionsor end plugs 15. In the trunnions 15 are anchored axially the ,ends' 1.8and 11 of a torsion spring 18 which encircles in somewhat wrapped aroundrelation the bar -61 and normally grips the bar frictionally againstrelative movement of the torsion spring and'bar. A foot lever 19 similarto the hand lever '48 passes through the rock shaft 14 and is securedthereto as by nuts 88 so that by depressing the foot lever 19 the rockshaft may be partially rotated to loosen the frictional grip of thetor-v sion springs 18 on the arcuate bars 61 and'per:-. mit relativemovement of the torsion springs and bars, thus permitting swinging ofthe links l3 and I4 upwardly as indicated in Fig. 7 toanyadjustedposition for the elevation of the board [I within the limits ofpossible relative movement of the torsion springs 18 on the bars 51.Thus as shown in Fig. '1 the drawing board ll may be used by thedraftsman comfortably when in standing position. When the foot lever 19is released the inherent resilience of the torsion springs 18 restoresthe springs to gripping position and this may be aided by a tensionco'ilspring 8|, hooked at one end, as at 82, to a projection '83 of thebracket 1|, and, at its other end, as at 84, to an arm 85 rigid withtherock shaft 14. The arms 85 similarly to the tems 40 may pass throughthe trunnions 15 and key these also to the rock shaft 14. f ,1 v y Inorder to carry a portion of theweight or the board I l and thus minimizethe eifortnece'ssary for raising the board, and. to .pre'ventjar whenthe board is lowered; a relatlvelyfheavy tension coil spring '86 iscarried at each inner side of the desk I0, hooked at its upperend asat'81 to a lug member 88 secured-as ,by sorew-s to the underface of thedesk top, and, at its other end, hooked, as at 90, to' another l'ugmember 9i fastened as by screws ,92'to-the'lower link (4, the springs 88being'under't'ension when 35 ,924 the drawing board II is lowered,.andas best shown in Fig. 3. a

It is intended to. be understood that the strut J2, constitutes arelatively fixed member, .and

the board II a relatively movable member, the

bracket 24 being carried by the relatively fixed member-l2 and. saidbracket havingan offset portion 28 spaced laterally of the'relativelyfixed member, and that the arcuate .bar 44 is disposed between therelatively fixed member l2 and the offset bracket portion 28. Similarly,'it is intended to be understood that the desk upright 59 constitutes arelatively fixed member and the link I4 a relatively movable member, thebracket H a being carried by the relatively fixed member '59 and saidbracket having an offset portion I3 spaced laterally of the relativelyfixed member, and that the arcuate bar 61 is disposed between therelatively fixed member 59 and the offset bracket portion 13. Thearcuate bar 44 or 61, as the case may be, is in either case carried byone of said members, in the case of the bar 44 by the relatively fixedmember I2, and in the case of-the bar 61 by the relatively movablemember l4. In each case, the arcuate bar 44 or 61, as the case may be,plays in a slot constituted by the space between the bracket offsetportion and the relatively fixed member, that is, the slot-like'spacebetween the bracket portion 28 and the relatively fixed member 12 in theone instance, and

the slot-like space between the bracket portion I3 and the relativelyfixed member 59 in the other instance.

It is to be understood that the invention is not intended to be limitedto details of construction here shown for illustrative purposes. Othermodifications may suggest themselves to those skilled in the art andhaving the benefit of the present disclosure. Furthermore, it is notintended that it be understood that all features of the presentdisclosure must be used conjointly, since it will be apparent to workersin the art that various combinations or subcombinations may at times beadvantageously employed.

Having described my invention, I claim- 1. Ina structure of the class.described embodying a relatively fixed member and a relatively movablemember, the combination of a bracket carried by the relatively fixedmember, said bracket having an offset portion spaced laterally of therelatively fixed member, and pro viding a slot-like space therebetweenan arcuate bar carried by one of said members and disposed between therelatively fixed member and the offset portion of said bracket, andadapted to play in said slot-like space a torsion spring encircling saidbar in normally gripping position thereon, a rotatable shaft journalledin said offset portion of the bracket, the ends of the torsion springbeing anchored in said shaft, and means for rotating the shaft to loosenthe torsion spring. I v

2. In a structure of the class described embodying a relatively fixedmember and a relatively movable member, the combination of a bracketcarried by the relatively fixed member, said bracket having an offsetportion spaced laterally of the relatively fixed member, an arcuate barcarried by one of said members and disposed between the relatively fixedmember and the offset portion of said bracket, a torsion springencircling said bar in normally gripping position thereon, a rotatableshaft journalled in 'said'offset portion of the bracket, the ends of thetorsion spring being anchored in said shaft, a lever carried by theshaft for rotating said shaft to loosen the torsion spring, an arm alsocarried by the shaft, and a tension spring having one end anchored toone of said members. and its other end to said arm to urge the shaft inthe opposite direction. a

3. In a structure of the class described embodying a relatively fixedmember and a relatively movable member, the combination of a bracketcarried by the relatively fixed member, said bracket having'an offsetportion spaced laterally of the relatively fixed member, an arcuate barcarried by one of said members disposed between the relatively fixedmember and the offset portion of said bracket, a torsion springencircling said bar in normally gripping position thereon, a rotatableshaft journalled in said offset portion, the ends of the torsion springbeing for each bar, and the said shaft is common to both torsionsprings.

4. In a device of the class described embody.- ing a base, a pair oflinks pivotally connected thereto at each side thereof, a pair ofcounterbalancing springs connected with the base and respectively withone of the links of each pair, a strut pivotally comiecting one end ofthe links of each pair and maintaining them in parallel relation, saidstrut being adapted to move downwardly with the links against the actionof the counterbalancing springs, that improvement therein comprising thecombination of an angular continuation of one of said links of eachpair, an arcuate bar secured at one end to each said link having saidcontinuation and at its other end to said continuation, a bracketcarried by the base at each side thereof, a shaft journalled in thebrackets, a torsion spring carried by the shaft at each end thereoffrictionally gripping each arcuate bar in wrapped around relationthereto, and means for rotating the shaft for loosening the frictionalgrip of the torsion spring on the bar.

5. In an adjustable stand of the class described embodying a base, apair of links pivotably connected thereto at each side thereof, a pairof counterbalancing springs connected with the base and respectivelywith one of the links of each pair, a strut pivotally connecting one endof the links of each pair and maintaining them in parallel relation, adrawing board carried by the struts, said struts being adapted to movedownwardly with the links against the action of the counterbalancingsprings, that improvement therein comprising the combination of anangular continuation on one of said links of each pair, an arcuate barsecured at one end to each said link having said continuation androtating the shaft for affecting the frictional grip of the torsionspring on the bar, said bars being adapted to play in the spaces betweenthe bracket ofiset portions and the base side during said movement of.said struts 6. In a device of the class describedembodying a base, apair of links pivotally connected thereto, a .counterbalancing springconnected at with one of the links at one of its ends and with saidcontinuation and at its other end to said continuation, .a rockablemember mounted on the base, a torsion spring carried by the rockablemember frictionally gripping said bar in wrapped around relationthereto, and means carried by the base at least in part through theintermediation of said rockable member for affecting the frictional gripof the torsion spring on the bar whereby the links may be swung on theirpivots for raising or lowering the strut.

7. In adevice of the class described embodying a relatively fixed memberand a relatively movable member having angularly related portionsmounted thereon, that improvement therein which comprises an arcuate barcarried by the relatively movable member through the intermediation ofsaid angularlyrelated portions, aerockable member mounted on saidrelatively fixed member, a torsion spring carried by the rockable memberand encircling said bar in wrapped around normally gripping relationthereto, and meanscarried by the relatively fixed member at least inpart through the intermediation of said rockable member foraffecting thegripping action of said torsion spring for relative movement of thefixed and movable members.

GEORGE E. FROELICH.

